I have a Nikon D80 I seem to remember having read somewhere that it should be possible to take photos in it using something called a second curtain technique. My question is does anybody know if this is so and how to go about it with the D80 (instructions for other camera models would be cool too)?

There are essentially two kinds of "slow synchro" flash: front curtain and rear curtain. Most point-and-shoot cameras only support front curtain. The flash fires immediately when you press the shutter button, and the shutter stays open a little while longer to capture more ambient light. Most "serious" cameras also offer rear curtain flash. When you press the shutter button, the shutter opens to capture ambient light. The flash fires at the end of the exposure.

The key difference between the two is that if your subject moves during the exposure, rear curtain flash makes the movement look like tail, an impression of where the subject has been. This generally looks best. Front curtain flash gives the opposite look, which tends to look weird.

A key difference from front (first) curtain is that movement blur will seem to end at the solid image instead of begin, so people and objects will appear to be moving in the direction they actually were rather than the opposite.

Second curtain sync is a flash-related term. In usual first curtain mode the flash is fired just after shutter opens, while in second curtain case the flash is fired just before shutter closes. This makes a difference with slow shutter speeds making the motion blur appear after moving objects instead of before them. Here's an example of second-curtain sync usage: http://www.flickr.com/photos/30093796@N07/4588904009/